[iMore Question]

If it helps I have an iPhone 7 Plus and MacBook (2015) both on the latest versions of iOS 10 and macOS Sierra 10.12

[Rob Phillips]

Welcome to iMore! I don't use personal hotspot all that often but it has always been inconsistent for me. If your MacBook isn't discovering your iPhone try turning personal hotspot off and back on. That usually worked for me.

[Just_Me_D]

Do you have a protective case on your iPhone? If so, remove it and then see if the connection improves.

[Tartarus]

I use my personal hotspot a few times per month when we're all together with the family and my Mom and Dad need internet.
Their data plan is only 1GB and I don't want them to use theirs when I'm around.
I've found that I have to go in the Hotspot settings from time to time when their iPhones both have been idle for some time.
By going to hotspot settings page it restarts sharing my data again.

TLR; go to Settings > Personal Hotspot from time to time to keep the connection between your iPhone and computer active.